The gas commonly used in balloons to make them float is helium. Helium is a colorless, odorless, and non-toxic gas that is lighter than air, allowing balloons filled with it to rise. Unlike hydrogen, helium is safe to use, as it is non-flammable and significantly reduces the risk of explosions. Helium is also prevalent in various industries, including medical applications, and is used for cooling superconducting magnets. The playful nature of helium balloons has made them a popular choice for celebrations, parties, and events, offering a whimsical and buoyant atmosphere when released into the sky.